Trigger mechanism for firearms



Oct. 15, 1929. F. K. YONNG 1,732,135

TRIGGER MECHANISM FOR FIREARMS Filed NOV. 1,1926

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Patented Oct. 15, 1929 UNITED STATES PATENT OFFICE FRANKLIN K. YOUNG, OFWIN'IHBOP CENTER, MASSACHUSETTS, ASSIGNOB TO AUTO- MATIC PISTOLS, INQ,OF DOVER, DELAWARE, A CORIORATION OF DELAWARE TRIGGER MECHANISM FORFIREARMS Application filed November 1, 1926. 'SeriaI No, 145,427.

This invention relates to an improvement in firearms and} particularlyto a trigger mechanism for automatic pistols.

Certain types of automatic pistols in common use are fired by tightlygripping the stock thereof and simultaneously applying pressure to asafety grip at the rear of said stock and to a trigger at the front ofsaid stock, the gripping action of the palm of the hand pressmg thesafety grip forwardly and operating a safety lock, thereby making itpossible to operate the trigger, and a rearward pressure of theforefinger upon said trigger operating the latter. As it is generallynecessary to apply a pressure of three and one-half pounds, or more,upon the trigger, before the pistol can be fired, it is very difficultto shoot accurately with this type of firearm, as there is a tendencyfor the aim to be destroyed when the trigger is pulled. It is the objectof this invention to so construct a pistol and the trigger mechanismtherefor, that in applying the pressure necessary to fire said pistol,there will not be the tendency hereinbefore mentioned to destroy theaim, and to accomplish this result, the trigger is located at the rearof the stock, and the safety locking mechanism therefor is actuated fromthe front of said stock, the result being that the pressurerequired tooperate the trigger is exerted forwardly and the action of the hand infiring the pistol is more in the nature of a squeeze than formerly. 'Theinvention consists in a trigger mechanism for firearms as set forth inthe following specification and particularly as pointed out in theclaims thereof.

Referring to the drawings:

Figure 1 is a partial side elevation and partial central longitudinalsection of a pistol, a trigger mechanism embodying my invention beingillustrated in connection therewith, the hammer of the pistol beingillustrated in its rearward or cocked position.

Fig. 2 is a sectional view of the-trigger mechanism, the hammer beingillustrated in its forward or firing position.

Like numerals refer to like parts throughout the several views of thedrawings.

In the drawings, 5 represents a stock, 6 a

barrel and 7 a slide surrounding said barrel and movable longitudinallythereon. The slide 7 projects rearwardly be ond the rear end of thebarrel 6 and has a c amber 8 provided therein in which the breechmechanism of the firearm is located.

The firearm illustrated is of a type in which the slide and breechmechanism are forced rearwardly by the explosion of the cartridge, andthe forward portion of the barrel 6 is reduced at 9, thereby forming aspace 10 in which a recoil spring 11 is mounted, said spring surroundingthe portion 9 of said barrel. The spring 11 at its rear end engages ashoulder 12 formed upon the barrel 6 and at its forward end said springengages a shoulder 13 provided upon the slide 7 in a manner tending toforce said slide forwardly upon said barrel following the rearwardmovement thereof.

The mechanism hereinbefore described, together with the breech mechanismpreviously mentioned, form no part of this invention and a detaileddescription is therefore not necessary. The breech mechanism is similarto the mechanisms that have been described in re vious patents grantedto me No. 1,157, 50, dated October 26, 1915, and No. 1,517,483, datedDec. 2, 1924, to which. reference may be had fora complete description.Briefly described, however, this mechanism embodies therein a lockingsleeve 14, which is both reciprocable and rotatable in the chamber 8behind the barrel 6; a yieldable bolt head 15 mounted in a recess 16 atthe forward end of the locking sleeve, and an inertia member ,17locatedwithin a bore 18 which extends forwardly from the rear end ofsaid locking sleeve. The bolt head 15 is located directly at the rear ofa cartridge 19 when the latter is located in the firing chamber 20 ofthe barrel 6, the forward extremity of said bolt head contacting withthe rear extremity of said cartridge, and the rear extremity of saidbolt head contacting with the front extremity of said inertia member,and the rearward thrust caused by the recoil when the cartridgeexplodes, is transmitted to the bolt head 15 and from thence totheinertia member 17 operating the breech mechanism for purposeswellknown to those versed in the art, and includend of said firing pin beingadapted to engage the percussion cap of the cartridge 19, and a spring23 surrounds said firing pin and acts to normally hold said firing pinout of engagement with said cartridge.

The hammer 21 is pivoted at 24 at the rear of the stock 5 and a strut 25is pivotally attached at one end thereof at 26 to said hammer, while theother end of said strut is provided with a rounded extremity whichprojects into a tapered recess 27 provided in the upper extremity of acap 28 secured to the upper end of a main spring 29, said cap and mainspring being located within a housing 30 at the rear of the stock 5. Thehammer 21 is held in its cocked position as illustrated in Fig. 1 by asear 31 pivoted at 32 tothe stock 5, and a spring 33 acts to always holdthe upper extremity of said sear against the peiphery of the hammer 21and hold said sear in engagement with a notch 34 formed in the peripheryof said hammer.

A trigger 35 is provided for the hammer 21, and said trigger ispivotally mounted upon the stock 5 at 36 at the rear of and below saidhammer. The trigger 35 extends from.- a point adjacent to the hammerdownwardly at the rear of the stock 5 and is curved forwardly anddownwardly in order that it may fit and be gripped by the palm of thehand, and a spring 37 acts to normally hold said trigger in the positionillustrated inFig. 1, at which time a stop 38 at the lower extremity ofsaid trigger engages a portion of the main spring housing. The trigger35 has a projection or finger 39 formed integral therewith andpositioned to engage a surface40 of the sear 31,

and when said trigger is pressed forwardly, said finger will cause thesear to be rocked upon its pivot 32, thereby disengaging the up perextremity of said sear from the notch 34 of the,hammer 21 and releasingsaid hammer from its cocked position, at which time the main spring 29acting through the strut 25 will force said hammer against the firingpin 22, thereby exploding the cartridge that is located within thefiring chamber 20.

The strut 25 has a camportion 4l-formed at the rear thereof, and saidcam portion is adapted to engage a surface 42 provided upon the trigger35, and when the hammer 21 .is moved to its cocked position, the strut25 in moving downwardly will engage the surface 42 of said trigger andforce the latter rearwardly until the stop 38 engages the main springhousing.

A safety locking mechanism 43 is provided for the trigger 35 to preventthe latter from being operated accidentally, and said look ing mechanismembodies therein a finger piece 44 which is slidably mounted in a recess45 located at the front of the stock 5. A yoke portion 46 projectsrearwardly from the finger piece 44, extending around the cartridgemagazine casing 47, and at the rear of 'said yoke a detent 48 isprovided and adapted to engage a similar detent 49 formed upon thetrigger 35.

When the hammer 21 is located in its cocked position, as illustrated inFig. 1, the upper extremity of the detent 49 engages the lower extremityof the detent 48 and the trigger 35 is prevented from being movedforwardly. VVh-en pressure is applied rearwardly upon the finger piece44, the detent 48 is forced rearwardly out of engagement with the detent49 and forward pressure upon the trigger 35 will cause the detent 48 toenter a notch 50 formed at the rear of the yoke 46.

A spring 51 is located within the recess 45 at the rear of the fingerpiece 44, and said spring acts to always force the lockin mechanism 43forwardly into the position illustrated in Fig. 1. A portion 52 of theyoke46 engages the magazine casing 47 at the rear thereof and limits theextent to which the locking mechanism 43 may move forwardly within thestock 5.

The general operation of the trigger mechanism hereinbefore specificallydescribed is as follows: Assuming that the various parts are in theposition illustrated in Fig. 2 with the hammer in its forward position,and it is desired to shoot the pistol, the action is as follows With thehand grasping the stock 5,

the thumb is placed upon the hammer 21 and the latter is movedrearwardly upon its pivot 24 forcing the strut 25 downwardly against theaction of the main spring 29. During the downward movement of the strut25 the cam portion 41 formed upon said strut engages the surface 42 ofthe trigger 35 and positively forces said triggerrearwardly until thestop 38 atpthe lower end thereof engages the wall 30 of the main springhousing. In this posi tion the locking mechanism 43 will be located inits forward'position as illustrated in Fig.

1, and the detent 48 at the rear end thereof will engage the detent 49formed upon the t'rigger35 in a manner to prevent a forward movement ofsaid trigger tending to operate the sear to release the hammer untilsuch time as said trigger is released .by the locln'ng mechanism.

With the hand now firmly gripping the ger to rock the sear 31 releasingthe hammer 21 and firing the cartridge 19 which is located within thefiring chamber 20 in the usualwell-known manner.

The actual forward movement that is required of the trigger to releasethe hammer 21 is very slight, and when the pressure is applied to saidtrigger, the lower portion of the strut 25 which is rounded and projectsinto the tapered recess 27 of the cap 28 yields for wardly, said roundedend sliding upon the inclined surface of the recess of the cap, thelatter yielding downward slightly against the tension of the spring 29.

The rearward thrust caused by the recoil of the exploding cartridge 19causes the breech mechanism to be forced rearwardly, automaticallythrowing out the exploded cartridge shell and allowing a fresh cartridgeto be thrown by the magazine mechanism and forward action of the breechmechanism into the cartridge chamber in a well-known manner, and therearward movement of the breech mechanism forces the hammer 21rearwardly into a cocked position where it will be locked b the lockingmechanism 43 as hereinbefore escribed. The pistol is then ready to befired again as hereinbefore set forth.

I claim: I

1. In a firearm a stock, a hammer pivotally attached thereto, a triggerlocated at the rear of said stock and operatively connected to saidhammer, and a lock normally obstructing the movement of said trigger andadapted when moved rearwardly to permit a forward movement of the latterto release said hammer from its cocked position.

2. In a firearm a stock, a hammer pivotally attached thereto, a scaradapted to hold said hammer in its cocked position, a trigger located atthe rear of said stock and adapted to operate said sear, and a locknormally obstructing adapted when moved rearwardly to permit theoperation of said trigger and sear'to release said hammer from itscocked position.-

3. In a firearm a hammer, a sear for said hammer, a trigger adapted tooperate said scar, and a spring-actuated strut o eratively connected tosaid hammer and having a cam portion formed thereon engaging saidtrigger and adapted to move the latter into a firing position when saidhammer is moved to its cocked position.

4. In a firearm a stock,

sear for said hammer, a trigger provided with a finger thereon adaptedto operate said sear to release said hammer from its cocked position,said trigger also having a detent formed thereon, and a safety locknormally engaging said detent and obstructing the movement of saidtrigger in a forward direction and adapted, when actuated, to permit theoperathe movement'of said trigger and.-

tion of said trigger and sear to release said hammer from its cockedposition.

5; In a firearm a hammer, a sear for said hammer, a spring-actuatedstrut operatively connected to said hammer, and a trigger provided witha finger thereon adapted to operate said sear to release said hammerfrom its cooked position, said strut having a cam portion formed thereonengaging said trigger and adapted to move the latter into a firingposition when said hammer is moved to a cooked position.

6. In a firearm a hammer, a sear for said hammer, a spring-actuatedstrut operatively connected to said hammer, a trigger provided with afinger thereon adapted to operate said sear to release said hammer fromits cocked position, said strut having a cam portion formed thereonengaging said trigger and adapted to move the latter into a firingposition when said hammer is moved to a cooked position, and a lockingmechanism normally engaging said trigger and obstructing the movementthereof and adapted, when pressure is applied thereto, to permit theoperation of said trigger and sear to release said hammer from itscocked position.

7. In a firearma hammer, a sear for said hammer, a spring-actuated strutoperatively connected to said hammer, a trigger provided with a fingerthereon adapted to operate said sear to release said hammer from itscocked position, said strut having a cam portion formed thereon engagingsaid trigger and adapted to move the latter into a firing position whensaid hammer is moved to a cooked position, said trigger also having adetent formed thereon, and a safety lock normally engaging said detentand obstructing the movement of said trigger and adapted when actuatedto permit the operation of said trigger and sear to release said hammerfrom its cocked position.

In testimony whereof I have hereunto set 111 hand.

y FRANKLIN K. YOUNG.

a spring-actuated hammer pivotally attached to said stock, a

